Magnesia plaster having powdered peanut shells as a constituent



Patented Nov. 2, i922.

ROKUSABURO YAIVIAMOTO, F OSAKA, JAPAN.

MAGNESIA PLASTEB HAVING POWDER/ED PEANUT SHELLS AS A CONSTITUENT.

life Drawing.

To all whom a may concern:

Be it known that Bonus-mono Yiiuixaio- To, subject of the Emperor of Japan, residing at No. 558, Kizu, lmamiya-machi, Nishinari-gun, Osaka-prefecture, Japan, has invented certain new and useful Improvements in Magnesia Plaster having Powdered Peanut Shells a Constituent, ol which the following is a specification.

This invention relates to improvements in magnesia plaster having powder of peanut shell as one of its constituents, and is characterized by the facts that powder of pea-nut shell is used instead of powder of leather waste or of cork hitherto used, and that lead acetate is added thereto for the purpose of utilizing the oil contained in pea-nut shells as a drier or siccative without adding any other oils; The object of the invention is to produce a good drier from powdered pea-nut shells by. causing manganese oxide and lead oxide to act upon oil contained in pea-nut shell, the manganese oxide usually existing in magnesia or magnesium oxide obtained by roasting 'magnesite and the lead oxide being obtained by chemical action of lead acetate added to magnesium oxide. Thus by such drier, the hygroscopic property, that is one of the defects of magnesia plaster, is greatly (lecreated. At the same time, magnesium acetate produced by chemical action of lead acetate upon magnesium oxide serves as an antiseptic as well as deodorizer upon the wood constituent used for composing the plaster.

Known magnesium plaster is made by mixing proper quantities of two or more of saw dust, wood powder, granular cork, cork-powder, leather waste or asbestos with magnesia or magnesium oxide and kneading the mixture with the addition of concentrated solution of magnesium chloride, or to which, when containing resins or oily substances as binding substances, is added lead acetate, magnesium chloride etc., for rendering the plaster water proof. But such known plaster -is objectionable owing to its poor water-proof property. The chief object of the invention is to improve this hygroscopic property of the plaster, as well as to utilize a very cheap plentiful and.

equally elastic raw material as a substitute for cork powder or leather 'waste. At the same time, it is proposed to utilize the oil Application filed September '18, 1920.

Serial No. 411,076.

contained in pea-nut shell in the proportion of approximately 6 per cent as a good drier. -For this purpose, a proper quantity of lead acetate is added which acts upon magnesium oxide and produces magnesium acetate and magnesium oxide. The latter acts upon the pea-nut oil, together with manganese oxide which is usually found in magnesia, and thus there is produced a good drier. Therefore magnesia plaster produced according to this invention is of low moisture absorptive quality and is devoid of a film of surface moisture even in rainy season. Moreover, magnesium acetate'serves well as an antiseptic as well as a deodorizer upon the wood constituent in the composition utilizing saw dust, wood powder and powder of pea-nut shell and like materials.

Example.

I. Lower coating; the mixture of Saw dust Asbestos -s 10%. Magnesia 40%.

is kneaded together with concentrated solution of Baum. viz. 44% solution of magnesium chloride dissolved in dilute or 2 or 3%.solution of lead acetate.

[1. For the upper coating, the mixture of-- Magnesia Powder of pea-nut shell 5%. Asbestos 10%. Pigment 5%.

is kneaded together with concentrated or 44% solution of magnesium chloride dissolved in dilute or 2 or 3% solution of lead acetate. The upper coating is visible, so it must be kept in perfectly dried state and its hygroscopic property is greatly objectionable. Therefore, for this coating powdered pea-nut shells are used. The use of lead acetate in the lower coating is for the purpose of increasing the durability of the wood material used.

it will of course be understood that, with out departing from the scope of the invention, the kinds of raw materials and their percentages may be modified according to the nature of the use to which the plaster is to be put, whether wall or floor, for instance and their positions so that the proper hardness will be given to the plaster, so

far as the characteristic point of using powlution of lead acetate of approximately 2%, 10 der of peaq-nut shell is maintained. substantially as set forth.

-Wha't I claim is: In testimony whereof he aflixes his sig- Magnesia plaster consisting of a comnature in the presence of two witnesses. 5 position of fibrous materials 10%, magnesium oxide 40% and pigment 5% with the ad- ROKUSABURO YAMAMOTO' dition of powdered pea-nut shells 5% knead- Witnesses: ed with concentrated solution of magnesium H. J. NEWTON,

chloride 44% Baum dissolved in dilute so- S0111) MORINE. 

